The Gene Expression Core is designed to provide the following services to the group. (a) Oligonucleotides will be synthesized upon request. They will be purified and checked for purity. The sequences of the oligonucleotides will be automatically checked with our database for sequence identity with (i) other oligonucleotides ordered through the core and (ii) with known DNA/protein binding sequences. (b) We propose to supply additional core instrumentation designed to facilitate both extract purification and plasmid and virus preparations. In addition instrumentation will be obtained to support transient transfection analysis, cloning and screening and also database searching. (c) The core will maintain a large inventory of enzymes (this will be integrated with the ongoing DRTC-supported DNA core), as well as kits, expression vectors, libraries and bacterial/yeast strains. In addition we propose to accumulate a stock of identified DNA-binding proteins for comparison purposes. (d) The core will prepare transcription extracts, as well as perform large-scale cell preparations for factor isolation purposes.